This application seeks a five-year continuation of the panel data collections of the Monitoring the Future (MTF) study, an ongoing epidemiological and etiological research and reporting project begun in 1975. In addition to being a basic research study, MTF has become one of the nations most relied upon sources of information on trends in illicit drug, alcohol, and tobacco use among American adolescents, college students, and young and middle-aged adults. This application seeks continuation of the mail follow-up surveys of high school graduates (augmented with internet options) at modal ages 19-30, 35, 40, 45, 50, and now 55. The companion main application seeks to continue the in-school data collections and to support the analysis of all of the data in the study, including past and future panel data. (NIDA requests that the study seek continuation funding through two separate applications, as it has done in the last two rounds.) The study's cohort-sequential longitudinal design permits the measurement and differentiation of three types of change-age (developmental), period (historical), and cohort. Each has different determinants, and all three types of change have been shown by MTF to occur for most drugs. Factors that may explain historical trends and cohort differences also are monitored. MTF is designed to document the developmental history and consequences of drug use and related attitudes from adolescence through middle adulthood, and to determine the individual and contextual characteristics and social role transitions that affect use and related attitudes. Research on risk and protective behaviors for the transmission of HIV/AIDS among adults ages 21-40 also will be continued. All of this work will be extended to new years, cohorts, and ages under this application and the companion main application. The study will examine the importance of many hypothesized determinants of drug use (including attitudes and beliefs and access), as well as a range of potential consequences (including physical and psychological health, status attainment, role performance, and drug abuse and dependence). Impacts of some policy changes on adolescents and young adults will be evaluated, including those of the new FDA cigarette labeling requirements. MTF will experiment with the use of internet response methods and pursue several new approaches to making its panel data more accessible to other investigators. The study's very broad measurement covers (a) initiation, use, and cessation for over 50 categories and sub-categories of licit and illicit drugs, including alcohol and tobacco; (b) attitudes and beliefs about many of them, perceived availability, and peer norms; (c) other behaviors and individual characteristics; (d) aspects of key social environments (home, work, school) and social role statuses and transitions; and (e) risk and protective behaviors related to the spread of HIV/AIDS. Results will continue to elucidate drug use from adolescence through middle adulthood-including the introduction of new drugs-with major implications for the policy, research, prevention, and treatment agendas. PUBLIC HEALTH RELEVANCE: This research project will continue the longitudinal study of smoking, drinking, and illicit drug use among nationally representative samples of high school graduates, as part of the ongoing Monitoring the Future study. American college students will be covered in this study. Panels drawn from each high school graduating class since 1976 will be followed across the life course, ranging up to age 55, to study patterns of substance use, possible causes, and long-term consequences. Such knowledge, as well as the differentiation of changes in drug use that occur with age, across historical periods, and between class cohorts, will increment our scientific understanding of these behaviors and inform prevention strategies and national drug use policy more generally.